The only way that worked was to reinstall Windows 10 through the settings. I tried every advice I ever got using the registry, command prompt, etc. but NOTHING ever worked. Before I took my computer to a repair shop, I decided to renew Windows 10. After it worked on it for many hours, I reinstalled all my apps and music and photos as they were before. Then I checked the Windows update and it was actually working. The laptop, which is 3 years old, is acting like it is new. Luckily it has a terabyte of hard drive space so I am in good shape now.